Division of Pain Medicine, Mantha Heart Clinic, Barkatpura, Hyderabad, India.
Division of Cardiology, Mantha Heart Clinic, Barkatpura, Hyderabad, India.
Medicine (Baltimore). 2021 Aug 13;100(32):e26916. doi: 10.1097/MD.0000000000026916.
Asian Indians have a genetic predisposition to atherothrombotic risk. common carotid intima-media thickness (CCIMT) measured by ultrasound is a quantitative marker for atherosclerotic burden and a derived variable, that is, "CCIMT statistical Z-score (Z-score)" is useful for better quantification. The association between vitamin D deficiency and atherosclerosis is inconclusive. Since, vitamin D deficiency is highly prevalent in India, there is a need to study its relative contribution to subclinical atherosclerotic burden.This prospective cross-sectional study (n = 117) in apparently healthy individuals aged 20 to 60 years sought to identify the determinants of CCIMT Z score with CCIMT measured by "echo-tracking" method. A multivariable linear regression analysis was done with CCIMT Z score as dependent variable and the following as independent variables: age, body mass index, waist-to-height ratio, total cholesterol to HDL ratio (TC-HDL ratio), serum vitamin D3 levels (ng/mL), sex, diabetes mellitus, current cigarette smoking status. A diagnostic prediction model was also developed with a threshold value of 1.96 for CCIMT Z score.The mean (SD) for calendar age (y) was 40 (8). There were 26 (22.22%) individuals in sample with CCIMT Z score ≥1.96 (advanced stage) of whom 14 (23.33%) were <40 y (n = 60). The mean score was 1.28 (90th percentile) in the entire sample. Vitamin D3 deficiency with a mean (SD) blood level (ng/mL) of 14.3 (6.4) was noted and prevalence of deficiency was 81%. The final model wasCCIMT Z-score = 0.80 + (0.841 × current smoking = 1) + (0.156 × TC-HDL ratio) - (0.0263 × vitamin D3 blood level in ng/mL).The decreasing order of association is smoking, TC-HDL ratio, and vitamin D3. With the model, likelihood ratio (95% CIs) was better for positive test 3.5 (1.23-9.94) than that for a negative test 0.83 (0.66-1.02).Internal validation with Bootstrap resampling revealed stability of baseline diagnostic variables.There is substantial subclinical atherosclerotic burden in Indian setting with independent contribution by vitamin D deficiency. The model is valuable in "ruling-in" of the underlying advanced atherosclerosis. The study is limited by convenient sampling and lack of external validation of the model.
亚洲印第安人易患动脉粥样硬化血栓形成风险。通过超声测量的颈总动脉内膜中层厚度（CCIMT）是动脉粥样硬化负担的定量标志物，也是衍生变量，即“CCIMT 统计 Z 分数（Z 分数）”有助于更好地定量评估。维生素 D 缺乏与动脉粥样硬化之间的关联尚无定论。由于印度的维生素 D 缺乏症非常普遍，因此需要研究其对亚临床动脉粥样硬化负担的相对贡献。本研究为前瞻性横断面研究（n=117），纳入年龄在 20 至 60 岁的看似健康个体，旨在通过回声跟踪法测量 CCIMT 来确定 CCIMT Z 评分的决定因素。使用多变量线性回归分析，将 CCIMT Z 评分作为因变量，将以下因素作为自变量：年龄、体重指数、腰围身高比、总胆固醇与高密度脂蛋白比值（TC-HDL 比值）、血清维生素 D3 水平（ng/ml）、性别、糖尿病、当前吸烟状态。还建立了一个诊断预测模型，以 CCIMT Z 评分的阈值为 1.96。（n=60）。在样本中，有 26 名（22.22%）个体的 CCIMT Z 评分≥1.96（晚期），其中 14 名（23.33%）年龄<40 岁（n=60）。整个样本的平均（SD）年龄为 40（8）岁。维生素 D3 缺乏症的平均（SD）血水平（ng/ml）为 14.3（6.4），缺乏症的患病率为 81%。最终模型为：CCIMT Z 评分=0.80+（0.841×当前吸烟=1）+（0.156×TC-HDL 比值）-（0.0263×维生素 D3 血水平，ng/ml）。关联的降序为吸烟、TC-HDL 比值和维生素 D3。使用该模型，阳性检验的似然比（95%置信区间）为 3.5（1.23-9.94），优于阴性检验的 0.83（0.66-1.02）。使用 Bootstrap 重采样进行内部验证显示，基线诊断变量稳定。在印度，亚临床动脉粥样硬化负担很大，独立于维生素 D 缺乏症。该模型对于潜在的晚期动脉粥样硬化的“确诊”具有重要价值。本研究的局限性在于方便取样和缺乏模型的外部验证。
